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Welcome to our Head Gardener’s Journal

In this monthly column, we will share technical aspects of our work and also keep you up to date about ongoing projects. If there is any topic you might want to hear more about, please ask during your next visit!

Planting Bulbs in Grass

While bulbs in borders can be planted throughout the autumn, bulbs in grass are planted at the end of September or beginning of October, before the grass becomes too wet.

Depending on the size and nature of the bulbs, different techniques are used.

Bulbs which look best in clusters are planted into grass flaps which have been dug with a spade. The size and depth of the flap is determined by the size of the bulb. For crocus bulbs, we dig a hole of about 15 cm square and a depth of about 12 cm.

Digging planting holes for crocus

The crocus bulbs are planted in groups of 12 and covered with hot chilli powder, which, as reported in January 2017, is a very effective deterrent for rodents. The flap is closed, and more chilli powder scattered onto the surface. The surface treatment is repeated during the winter, wherever scratching by animals is apparent.

Crocus planting and protection with chilli powder.

Small bulbs which look better as individuals, such as scilla siberica, are planted into holes made with a crowbar. The holes are then filled back with compost. There is no need for chilli powder as Scilla bulbs do not get attacked by rodents.

Making holes with a crowbar
Having planted the bulbs, the holes are closed with compost

The greatest challenge by far is to plant large bulbs such as camassias and allium hollandicum: These bulbs which have a diameter of about 6 cm must be planted individually, at least 20 cm deep. This cannot be done with a spade or crowbar but requires an auger drill. The drill is petrol-driven and vibrates very strongly, which is why it needs two people to operate it. Given that we are planting several thousand of these bulbs every autumn, this is a very strenuous task!

Auger drill
Camassias and alliums ready for planting